Provide more information on backend calls. Backward compatible with drush5.
Move dynamic help bits out of help hook and into help_alter() hook. The help hook is called before a site is picked so you you can't check for major_version().
Remove unused variable.
sql commands - Dynamic help needs to be in help_alter() hook if it depends on the major version of drupal.
Actually, we have to declare all the options statically since most sql- commands don't bootstrap to SITE. We unhide the options dynamically in help_alter().